10/1/2016 | BY Resident Review Contributors

Pediatric Trauma Questions

Question 1:

This 7 year old male presents with mild limitation of left elbow range of motion following an ill-defined injury two years ago. Bilateral forearm x-rays are demonstrated (Figure 1a, 1b). Which of the following is most likely to be true?

A. She suffered a pulled elbow 2 years ago.
B. She has a congenital abnormality of her radio-capitellar joint.
C. Treatment will consist of a Bell-Tawse reconstruction.
D. Surgery is indicated if she fails 6 months of aggressive physiotherapy.
E. Treatment will consist of an ulnar osteotomy, open reduction of the radiocapitellar joint, +/- annular ligament reconstruction, +/- radiocapitellar pin.
 

Figure 1a

Figure 1b
 
Preferred Response: E
The child has a chronic Monteggia fracture dislocation that was not treated. Precise recommendations for the management of these injuries continues to be debated. A common approach is to correct the persistent angulation and shortening of the ulna, openly reduce the radiocapitellar joint, and perform an annular ligament reconstruction if radiocapitellar instability persists following ulnar osteotomy and radial head reduction. Finally, a pin can be placed across the radiocapitellar joint if annular ligament reconstruction does not provide adequate stability.

Pulled elbow is less common at 5 or more years of age and is unlikely to lead to any long term ROM deficit or x-ray abnormality. The history of this child’s injury, associated with apex volar bowing of the ulna and a normal looking but dislocated radial head, is most suggestive of a missed Monteggia or Monteggia variant. A (modified) Bell-Tawse reconstruction may be part of this child’s surgical management, but not in isolation. Physiotherapy will not be able to correct the deformity of the ulnar diaphysis or radiocapitellar dislocation.
 
Recommended Reading:

• David-West KS, Wilson NIL, Sherlock DA, Bennet GH. Missed Monteggia injuries. Inury. 2005 Oct;36(10):1206-9
• Goyal T, Arora SS, Banerjee S, Kandwal P. Neglected Monteggia fracture dislocations in children: a systematic review. J Pediatr Orthop B. 2015 May;24(3):191-9.

 

Question 2:

A 10 year old girl fell while doing gymnastics and sustained a posterolateral elbow dislocation. Following reduction of the dislocation, an absolute indication to proceed with open reduction and internal fixation of the fracture shown in figure 2 is:
A. Displacement of the fracture more than 0.5cm on the AP radiograph.
B. Displacement of the fracture more than 75% of the fracture bed as determined on a CT scan.
C. Entrapment of the fracture fragment in the elbow joint.
D. The injury occurring in the dominant arm of an overhead throwing athlete.
E. An acute ulnar nerve neuropraxia.
 
Figure 2

Preferred Response: C
 
Discussion:  Figure 2 shows an elbow dislocation associated with a medial epicondyle fracture. The source of the fracture fragment is often difficult to appreciate on injury X-Rays. Medial epicondyle fractures are the most common fractures associated with elbow dislocations in children, and orthopedic surgeons should have a high index of suspicion for the injury. Following relocation of the elbow joint, absolute indications for fixation of a medial epicondyle fragment include open fractures and the fragment being entrapped within the joint. There are several relative indications (which remain somewhat controversial), including ulnar nerve neuropraxia, elbow instability, athletes who place a high level of stress on the elbow, and significant displacement of the fragment. No agreed-upon definition for how much displacement is too much has been established. Studies evaluating the fractures on CT scans have shown that the fragment can be displaced much more significantly than appreciated on an AP elbow X-Ray. Though there has been a general trend toward more operative fixation for these fractures, currently available long-term outcome studies have failed to establish a clear benefit for operative fixation versus conservative management.
 
Recommended Reading:

• Edmonds EW. How displaced are “nondisplaced” fractures of the medial humeral epicondyle in children? Results of a three-dimensional computed tomography analysis. JBJS 2010;92-A(17):2785-91.
• Gottschalk HP, Eisner E, Hosalkar HS. Medial epicondyle fractures in the pediatric population. JAAOS 2012;20(4):223-232.
• Pathy R, Dodwell ER. Medial epicondyle fractures in children. Curr Opin Peds 2015;27(1):58-66.

Question 3:

A 14 year old boy injured his left knee while playing basketball. A lateral radiograph of the knee is show in the figure. Of the following, the most common finding encountered during assessment and treatment of the fracture shown in figure 3 is:

A. Patellar tendon avulsion from the tibial tubercle.
B. Genu valgum following growth arrest of the proximal tibial physis.
C. Recurvatum of the knee following growth arrest of the proximal tibial physis
D. Unrecognized anterior cruciate ligament tear.
E. Development of a compartment syndrome.
 
 
Figure 3
 
Preferred Response: E
 
Discussion: Figure 3 shows a tibial tubercle fracture. Fractures of the tibial tubercle result from avulsion of the anterior proximal tibial fragment attached to the patellar tendon, and are felt to be due to an excessive eccentric load placed across the knee joint. Patients typically have focal pain at the fracture site, marked edema, a palpable defect, and the inability to perform a straight leg raise. Associated injuries can include meniscal tears, but do not usually include damage to the cruciate ligaments. The patellar tendon can be avulsed from its insertion on the tibial shaft, but it remains attached to the tibial tubercle fragment. Growth arrests following tibial tubercle fractures are possible, but because these injures most commonly occur in mid to late adolescence, close to the cessation of growth, it is rare to develop a clinically-significant deformity. The soft tissue stripping and edema at the site of the origin of the anterior compartment of the leg make compartment syndrome a significant concern with these injuries, with documented rates as high as 10%.
 
Recommended Reading:

• Pandya NK, Edmonds EW, Roocroft JH, Mubarak SJ. Tibial tubercle fractures: complications, classification, and the need for intra-articular assessment. J Pediatr Orthop. 2012 Dec;32(8):749-59.
• Pretell-Mazzini J, Kelly DM, Sawyer JR, Esteban EM, Spence DD, Warner WC Jr, Beaty JH. Outcomes and Complications of Tibial Tubercle Fractures in Pediatric Patients: A Systematic Review of the Literature. J Pediatr Orthop. 2016 Jul-Aug;36(5):440-6.

 
Question 4:

A 10 year old boy is struck by a car running across the street.  He has isolated left knee pain.  X-rays are shown in figure 4 a,b.  The patient is taken to the operating room and undergoes open anatomic reduction with placement of three lag screws across the metaphyseal spike with no fixation that crosses the physis (figure 5).  The patient heals uneventfully.  On the day of presentation, his family should be cautioned about possible growth disturbance.  Which of the following growth arrest patterns is most likely to occur?
 
A. Partial growth arrest resulting in genu recurvatum.
B. Complete growth arrest at the distal femur resulting in leg length discrepancy only.
C. Partial growth arrest resulting in genu varum deformity.
D. Partial growth arrest resulting in genu valgum deformity.
E. Partial growth arrest resulting in genu procurvatum.
 
  
 Figure 4a                         Figure 4b

Figure 5
 
Preferred Response: D
Since the metaphyseal spike is on the medial side in this clinical scenario, the physis on that side will be spared (not involved).  For that reason, if the patient develops a growth problem, it is likely to involve the lateral half of the physis and therefore, result in a genu valgum deformity.
 
Recommended Reading:

• Roberts JM: Fractures and dislocations of the knee.  In Rockwood CA Jr, Wilkins KE, King RE, eds: Fractures in children, Philadelphia, 1984, Lippincott.

 

Question 5:

A 5 year old female presented to the ED with chief complaint of left elbow pain after falling off of her bike the evening prior to presentation. On exam she was mildly swollen and tender over the lateral distal humerus. Radiographs are shown in figures 6 a-c. What treatment option offers the lowest rate of complications in these fractures that are displaced >2 mm.

A. Long arm cast
B. Closed reduction and long arm cast
C. Closed reduction percutaneous pinning, long arm cast
D. Closed reduction percutaneous pinning, elbow arthrogram, long arm cast
E. Open reduction internal fixation, long arm cast


       
Figure 6a                Figure 6b                                Figure 6c

Preferred Response: D: Closed reduction percutaneous pinning, elbow arthrogram, long arm cast

Figure 7

Closed reduction and percutaneous pinning is a good option when you can confirm that the articular surface of the distal humerus is aligned well with no step off or gap. Elbow arthrogram can help to assess the articular surface and make sure that the elbow does not require an open reduction (figure 7).
A study by Pennock et al compared closed reduction and percutaneous pinning to open reduction and internal fixation for lateral condyle fractures that were displaced more than 2 mm.  They found all fractures healed within 12 weeks, OR time was less for the closed reduction group, complications were higher in the ORIF group than the CRPP group but these were not significantly different. There were no major complications in the CRPP group but there were 3 in the ORIF group including 1 case of AVN, 1 case of osteomyelitis and 1 refracture that required surgery.
 
 
Recommended Reading:

• Pennock AT, Salgueiro L, Upasani VV, et al. Closed Reduction and Percutaneous Pinning Versus Open Reduction and Internal Fixation for Type II Lateral Condyle Humerus Fractures in Children Displaced >2mm. J Pediatr Orthop 2015

 

Question 6:

A 4 year old boy fell off of his bike and injured his right elbow. He was placed into a splint by the ED staff and told to follow up with orthopaedic surgery in 1 week. His original x-rays are in figure 7 a-c. When he presented to clinic 10 days after injury what is the most important x-ray image to obtain to help determine treatment?

A. Lateral of the elbow
B. AP of the elbow
C. External oblique of the elbow
D. Internal oblique of the elbow
E. Lateral of the forearm

     
     Figure 7a                             Figure 7b                                          Figure 7c

Preferred Response: D Internal oblique of the elbow
 
  
Figure 8a                                Figure 8b

You can see in this very short splint, that wasn’t immobilizing the elbow well, that on the AP view it is hard to assess fracture displacement (figure 8a) but on the internal oblique radiograph (figure 8b) the fracture has displaced significantly ultimately requiring surgery .

A study by Song et al. evaluated 4 radiographic views along with CT scans for lateral condyle fractures. They found that the internal oblique view was most accurate for demonstrating fracture gaps and should be utilized in assessing lateral condyle fractures and making recommendations for surgery.
 
Recommended Reading:

• Song KS, Kang CH, Min BW, Bae KC, Cho CH. Internal oblique radiographs for diagnosis of nondisplaced or minimally displaced lateral condylar fractures of the humerus in children. J Bone Joint Surg Am. 2007 Jan;89(1):58-63.

 
 

Question 7:

A 7 year old male presents after a fall off of his scooter onto the left elbow. Upon arrival to the Emergency Department neurovascular examination is intact and compartments are soft. Injury AP and Lateral radiographs are shown in figure 9.

 
Figure 9
 
9 hours after presentation the patient is taken to the operating room for CRPP with lateral entry divergent 3-pin Kirschner wire construct anatomic alignment of the fracture in the sagittal plane but inability to close the medial fracture gap.  Immediate post-operative examination reveals significant hypoesthesia in the small finger and intrinsic hand weakness.  The next most appropriate step in treatment is:

A. Bivalving of cast to accommodate postoperative swelling.
B. Removal of most medial of the 3 Kirschner wires.
C. Observation with expectation for spontaneous recovery of ulnar neurapraxia.
D. Urgent return to operating room for open exploration of ulnar nerve and revision fixation.
E. Repeat examination in 6 hours once patient more alert and compliant.

Preferred Response: D
Urgent return to operating room for open exploration of ulnar nerve and revision fixation.

The most common neurologic injury associated with flexion type supracondylar fractures are injuries to the ulnar nerve, occurring in up to 19% of patients.  Inability to reduce the medial column fracture gap during CRPP warrants open reduction and percutaneous pinning via an anteromedial approach in order to extricate the incarcerated ulnar nerve from the fracture site.  Since the patient did not have preoperative ulnar nerve palsy and no medial pins were used in the case, the new onset post-operative  ulnar nerve palsy is most likely due to incarceration of the ulnar nerve in the medial fracture gap.

Recommended Reading: 

• Mahan ST, May CD, Kocher MS. Operative management of displaced flexion supracondylar humerus fractures in children. J Pediatr Orthop. 2007;27(5):551-556.
• Bouton D, Ho CA, Abzug J, Brighton B, Ritzman TF. The Difficult Supracondylar Humerus Fracture: Flexion-type Injuries.  Instr Course Lect. 2016;65:371-378.

 

Question 8:

Which of the following patients has a higher risk of developing compartment syndrome?

A. 4 year old boy with type 3 extension type supracondylar humerus fracture with palpable radial pulse
B. 5 year old boy with displaced supracondylar humerus fracture and non displaced distal radius and ulna fractures
C. 7 year old girl with displaced tibia fracture
D. 14 year old boy with displaced tibia fracture
E. 11 year old boy with closed displaced forearm fracture
 
Preferred Response: D
Adolescents with tibia shaft fracture are reported to have the highest incidence of compartment syndrome seen in children.  Displaced supracondylar humerus fractures with intact pulse develop compartment syndrome in about 0.1-0.3% of the cases. Presence of non displaced distal forearm fractures does not increase the chance of compartment syndrome in patients with supracondylar humerus fracture (floating elbow injuries). The chance of compartment syndrome in floating elbow injuries is high if the forearm fracture is displaced and is treated with casting.

Forearm fractures are at risk for developing compartment syndrome if they are treated within the first 24 hours with flexible nailing and if prolonged manipulation was used during the case.
 
Recommended Reading:

• Shore, B.J., et al., Acute compartment syndrome in children and teenagers with tibial shaft fractures: incidence and multivariable risk factors. J Orthop Trauma, 2013. 27(11): p. 616-21
• Hosseinzadeh P, Hayes CB. Compartment Syndrome in Children.  Orthop Clin North Am. 2016 Jul;47(3):579-87. doi: 10.1016/j.ocl.2016.02.004.

Question 9:

A 9 year old boy presents with displaced Salter Harris II fracture of the distal radius. Neurologic and vascular examination is intact at the time of presentation. Closed reduction and casting is performed under conscious sedation in the emergency room and anatomic reduction is achieved. Patient presents 6 hours later with severe pain and paresthesia in median nerve distribution. Paresthesia is confirmed by the examination. Forearm compartments are soft and the radial pulse in palpable. Cast is bivalved but the pain and paresthesia persists. What is the best next step in the management of this patient?

A. Closed monitoring for the next 24 hours
B. Fasciotomy of the volar and dorsal compartments of the forearm
C. Operating room for fixation of the fracture and carpal tunnel release
D. Discharge home with instruction for elevation and edema control
E. Measurement of forearm compartment pressures

Preferred Response: C
The vignette describes a patient with acute carpal tunnel syndrome after displaced physeal fracture of the distal radius. Early recognition and emergent treatment are the key to prevent future problems. This patient would be best treated with a carpal tunnel release and fixation of the fracture (to decrease the pressure needed by the cast to keep the fracture reduced). Soft compartments of the forearm and the distal location of the fracture make the diagnosis of forearm compartment syndrome unlikely.

Recommended Reading:

• Gillig JD, White SD, Rachel JN.  Acute Carpal Tunnel Syndrome: A Review of Current Literature. Orthop Clin North Am. 2016 Jul;47(3):599-607. doi: 10.1016/j.ocl.2016.03.005

 
Question 10:

A 12 year old boy comes in with closed isolated injury to right ankle after a football injury where a player hit his right foot which was planted on artificial turf.  He is neurovascularly intact and otherwise healthy.  Radiographs are shown below at presentation (figure 10 ) and after closed reduction and splinting under conscious sedation (figure 11). What is the next step in definitive treatment for this type of fracture and what is the correct counselling you should provide to the family regarding premature physeal closure?

Figure 10

Figure 11

A. Closely follow reduction with weekly radiographs and overwrap with cast material once swelling goes down since the reduction is acceptable and will not predispose the patient to high risk of premature physeal closure.
B. Closed reduction, percutaneous pinning of distal tibia fracture since the physeal alignment of less than 3mm displacement and articular alignment less than 2mm displacement can be verified on fluoroscopy.
C. Immediate epiphysiodesis distal tibia and fibula and ORIF because the risk of premature physeal closure of a distal tibia Salter-Harris IV fracture is 80% regardless of reduction achieved.
D. Open reduction, internal fixation of the distal tibia fracture because improving the alignment to less than 3mm physeal displacement and less than 2mm joint displacement will decrease the patient’s chances of premature physeal closure.
 
Preferred Response: D
Open reduction and internal fixation with improvement of alignment of the displaced distal tibia fractures in children are reported to decrease the occurrence of physeal arrest.

Recommended Reading:

• Barmada A, Gaynor T, Mubarak SJ. Premature physeal closure following distal tibia physeal fractures: a new radiographic predictor. J Pediatr Orthop 2003 Nov-Dec;32(6):733-9.
• Rapariz JM, Ocete G, Gonzalez-Herranz P et al. Distal tibial triplane fractures: long-term follow-up. J Pediatr Orthop 1996 Jan-Feb;16(1):113-8.